INTRAOPERATIVE UROKINASE AS AN ALTERNATIVE TO HEPARIN FOR PATIENTS WITH SUSPECTED HEPARIN-INDUCED THROMBOCYTOPENIA REQUIRING ARTERIAL RECONSTRUCTION - REPORT OF A CASE AND REVIEW OF THE LITERATURE

Patients with heparin-induced thrombocytopenia (HIT) require an altern ative antithrombotic treatment to heparin during arterial reconstructi on. Ancrod and Iloprost have been employed but are not readily availab le and carry the risks of systemic side effects (depletion of fibrinog en, hypotension). A patient with HIT in whom intraoperative intraarter ial urokinase (UK) was successfully utilized to enable safe arterial r econstruction is described. An 80 year old white female with diffuse a rteriosclerotic cardiovascular disease and multiple vascular reconstru ctions had thrombotic complications following use of heparin during tw o of her prior operations associated with documented thrombocytopenia and anti-platelet antibodies. She presented with limb-threatening isch emia which was evaluated with angiography revealing severe stenosis of the proximal left superficial femoral artery, occlusion of both anter ior tibial and peroneal arteries and several digital vessels, with int act posterior tibial runoff. A common femoral to mid-superficial femor al artery bypass was performed, utilising controlateral reversed great er saphenous vein, while being treated with aspirin and a continuous i ntravenous infusion of low molecular weight dextran. During the proced ure the clamped arteries were locally perfused with a high volume of d ilute UK solution to prevent blood stasis, and enable local delivery o f a thrombolytic agent. Although clot formation was observed in the op erative field, none occurred within the clamped arteries. A total of 1 91,200 units of UK were employed with no bleeding complications. Follo wing surgery the patient had a palpable pedal pulse and markedly impro ved perfusion of her toes. She was discharged on aspirin and coumadin on postoperative day five. It is concluded that for patients with HIT, systemic aspirin and dextran combined with local intraarterial UK are a simple and effective substitute for systemic anticoagulation with h eparin during arterial reconstruction.